Photometer.



H. E. IVES.

PHOTOMETER.

APPLICATION FILED APR.10. 191av 1,086,535; Patented Feb. 10, 1914 W/T/VESSES: lNVEA/TOI? W /Zerber/i /1 e.s W

a be given in connection with the accompany- UNITED 'STATEgPATENT OFFICE.

HERBERT E, IVES, 0F MOUNT AIRY, PENNSYLVANIA, ASSIGNOR TQ THE'UNITED GAS IMPROVEMENT COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION PHOTOMETER.

' Specification of Letters Patent. Application filed April 10,1913. Serial No. 760,150.

Patented Feb. 10, 1914'.

Photometers, of which the following is a specification.

The principal object of the present invention is to provide. ahand photometer which can be conveniently used by lamp inspectors and'othcrs, for ascertaining the candle power of street lamps and the like.

Other objects of the invention will appear from the following description which will ing drawings, forming part hereof and illustrating one embodiment of the invention,

. I and in which Figure 1, is a perspective view illustrating a hand photometer embodying features of the invention and showing in a general way how it may be used. Fig. 2, is a top or plan view, partly in. section, illustrating a portion of a photometer embodying features of: the invention, and Fig. 3, is a side View partly in section of the same.

In the drawings ,1 is a stall adapted to be held in one hand with one end in contact with a street light lantern or globe 2. This staff is graduated as at 3 and in'the graduations account is taken of the distance be tween the. end of the staif andthe source of light 4 to be tested, or in other words, of the distance between the light source 4 and the outside of the lantern or globe. The end of the stall is provided with a pad 5 which i when present prevents'slipping and avoids possible danger of breaking the glass of the globe or lantern.

6, isa photometer box and it is slidable on the stall.

In connection with the photometer chosen for illustration in the accompanying drawings 7 is the standard light, 8 are translucent glasses and 9 is a silvered glass or other appropriate partition having a clear or unobstructed opening 10.

11 and '12 are handle members pivoted together at .13 and whereof'one,-]12, is connected with the photometer box. The other handle element 11 is provided with an end 14: which operates when released by reason of the spring 15 as aclutch' to retain the photometer box 6 in any position to which it ,electric lamp, a storage battery l7 is provided. This battery is arranged to be carrled, for example, in the pocket of the operator. In the circuit 18 of the battery there is interposed a switch 19, one element of which is carried by the handle element '11 so that in the normal position of the handle element the circuit is broken and when the handle element is moved to take a reading the circuit is made and the lamp lighted. I

In use the operator may hold one end of the staff with one hand and place the other end of the staff against the lantern or globe of the street light. With his free hand the operator presses the handle elements together thus establishing the circuit and releasing the clutch element 14, lighting the standard light 7 and freeing the photometer box on the staff. The operator may then ascertain the candle power by comparison in the ordinary way and havin done this, the operator releases the hand e elements, thus breaking the circuit of the lamp 7 and locking the photometer box on the staff.

The operator at his convenience can then read the scale in respect to the pointer 16 and so ascertain the candle power.

The device as a whole is easily carried about and can be operated without making any measurements or requiring any supports.-' Of course, it will be understood that the device is intended to be used at night and in the absence of such surrounding artificial light as would be disadv'anta eous. These are conditions that render the evice particularly useful for lamp inspectors, whoby it can ascertain the condition of any street light accurately, quickly and without guesswork. a

It will be obvious to those skilled in the art to which my invention relates that modifications may be made in details of construction and arrangement, and hence I do not limit myself in regard to such matters or further than the prior state of the art may require, but

Having thus described the nature and objects of my invention, what I claim as new and desire to secure by Letters Patent is 1. A hand photometer comprising the combination of a staff adapted to be held in one hand with one end in contact with a.

street light lantern and graduated with respect to the light in the lantern, a'photometer box slidable on the staff, and means for retaining the box in any position in which it is put on the staff, whereby the box can be operated by the other hand, substantially as described.

2. A hand photometer com rising the combination of a graduated sta a photometer box slidable on the stafl", a'standard electric lamp and its portable battery and circuit, and means tending to lock the box and staff and, break the circuit and adapted when released to make the circuit, substantially as described.

3. A hand photometer com rising the combination of a graduated sta a photom tuated by said handle elements and adapted to clamp and unclamp the stafi and box,

5 substantially as described.

A. A hand photometer comprising the combination of a graduated staff, a photometer box slidable on the stafi, a standard electric lamp and its portable battery and circuit connections, and cooperating fixed and movable handle elements includingan electric switch, and a locking device, substantially as described.

5. A hand photometer comprising the combination of a stafl graduated in respect 'to a lantern and the light therein and provided with a padded end, a photometer box provided with fixed and movable cooperating handle elements, a standard electric light and its circuit connections and source of current, and a clutch and switch operated by the handle elements, substantially as described.

In testimony whereof I have hereunto signed my name.

HERBERT E. IVES. Witnesses CLHFURD K. CAssEL,

FRANK E. FRENCH. 

